FixedLengthUtil::FixedLengthAbstractIterator Class Reference

Structured line iterator for abstract data allowing efficient "pipelined" processing. More...

#include <FixedLengthAbstractIterator.qc.dox.h>

Inheritance diagram for FixedLengthUtil::FixedLengthAbstractIterator:

Public Member Methods
bool	checkTransition (*string from, *string to)
	A verification function to be called for each line. This method can be overridden to achieve a begin-to-end validation of the whole input file. More...
	constructor (AbstractLineIterator li, hash< auto > spec, *hash< auto > opts)
	Instantiates the FixedLengthAbstractIterator object. More...
*hash< auto >	getValue ()
	Returns the current record as a hash. More...
bool	identifyRecord (list< auto > rec_rule, string input_line)
	Attempts to identify a single record.
string	identifyType (string input_line)
	Identify a fixed-length line type using identifyTypeImpl(), that may be overridden if necessary. More...
*string	identifyTypeImpl (string input_line)
	Identify a fixed-length line type, given the raw line string. This method performs a lookup to a precalculated table based on line lengths (see constructor()). In case different criteria are needed, eg. when two line types in a spec have the same length and no unique resolving rule are specified, this method needs to be overridden, and will throw an exception, because the precalculated mapping will be empty. More...
bool	next ()
	Moves the current line / record position to the next line / record; returns False if there are no more lines to iterate. More...
auto	transform (auto value, hash< auto > type)
	parses the input value based on global configuration and the current field definition
Public Member Methods inherited from FixedLengthUtil::FixedLengthBase
	constructor (hash< auto > m_specs, *hash< auto > m_opts)
	Creates the object from the record specifications.
*hash< string, AbstractDataField >	getRecordType ()
	Returns the description of the record type, if any.

Static Private Member Methods
static *hash< auto >	checkOptions (*hash< auto > opts)
	Validate and prepare global fixed-length options. More...

Private Attributes
hash	m_resolve_by_length
	hash of type without rule, i.e.potentially conflicting records; key = record length, value = list of no-rule type names
Private Attributes inherited from FixedLengthUtil::FixedLengthBase
const	GlobalOptionMap
	Translates from global options to data provider options.
*hash< auto >	m_opts
	Global input or output options.
hash< auto >	m_specs
	The record specifications.

Detailed Description

Structured line iterator for abstract data allowing efficient "pipelined" processing.

Member Function Documentation

checkOptions()

static *hash< auto > FixedLengthUtil::FixedLengthAbstractIterator::checkOptions ( *hash< auto >  opts )

staticprivate

Validate and prepare global fixed-length options.

Parameters

opts	Options passed during class instantiation.

checkTransition()

bool FixedLengthUtil::FixedLengthAbstractIterator::checkTransition	(	*string	from,
		*string	to
	)

A verification function to be called for each line. This method can be overridden to achieve a begin-to-end validation of the whole input file.

Parameters

from	Type of previous line being processed
to	Type of the current line being processed

constructor()

FixedLengthUtil::FixedLengthAbstractIterator::constructor	(	AbstractLineIterator	li,
		hash< auto >	spec,
		*hash< auto >	opts
	)

Instantiates the FixedLengthAbstractIterator object.

Parameters

li	source line iterator
spec	Fixed-length line specification; see Specification Hash for more information
opts	Global options; see Global Options for more information

Exceptions

FIXED-LENGTH-UTIL-INVALID-SPEC

invalid record specification; invalid type or missing field length

getValue()

*hash< auto > FixedLengthUtil::FixedLengthAbstractIterator::getValue ( )

virtual

Returns the current record as a hash.

Example:

my hash $h = $i.getValue();

Returns

The current record as a hash with the following keys:

• "type": a string giving the record type name
• "record": a hash giving the parsed record data

Implements Qore::AbstractIterator.

identifyType()

string FixedLengthUtil::FixedLengthAbstractIterator::identifyType

(

string

input_line

)

Identify a fixed-length line type using identifyTypeImpl(), that may be overridden if necessary.

Parameters

input_line

Input line to be identified

Returns

the name of the record corresponding to the input line

Exceptions

FIXED-LENGTH-UTIL-NON-MATCHING-TYPE

input line cannot be matched to a known record

identifyTypeImpl()

*string FixedLengthUtil::FixedLengthAbstractIterator::identifyTypeImpl

(

string

input_line

)

Identify a fixed-length line type, given the raw line string. This method performs a lookup to a precalculated table based on line lengths (see constructor()). In case different criteria are needed, eg. when two line types in a spec have the same length and no unique resolving rule are specified, this method needs to be overridden, and will throw an exception, because the precalculated mapping will be empty.

Parameters

input_line

Input line to be identified

Returns

the record name or NOTHING if the input cannot be matched

Exceptions

FIXED-LENGTH-UTIL-NON-MATCHING-TYPE

input line cannot be matched to a known record or the input line's length does not match the expected length

next()

bool FixedLengthUtil::FixedLengthAbstractIterator::next ( )

virtual

Moves the current line / record position to the next line / record; returns False if there are no more lines to iterate.

This method will return True again after it returns False once if the file being iterated has data that can be iterated, otherwise it will always return False. The iterator object should not be used to retrieve a value after this method returns False.

Returns

False if there are no lines / records to iterate (in which case the iterator object is invalid and should not be used); True if successful (meaning that the iterator object is valid)

Note

that empty lines are ignored if "ignore_empty" option is in effect

Implements Qore::AbstractIterator.